The present invention relates to a skiing area specialized for artificial skis and a method for producing the same.
The present inventors have proposed an overlay member (i.e., a mat 1) to be used to form an artificial skiing slope in Japanese Patent Application Laid-Open No. Hei 6-10082.
This mat 1 is made of synthetic resin. As shown in FIGS. 1 to 5, a plurality of retainer projections 2 are integrally connected to ribs 11 which have a lower height than that of the retainer projections 2. Male connectors 8a and female connectors 8b are provided on each side of the mat 1. The size thereof is 1 meter long and 1 meter wide. Accordingly, the mat 1 is laid for use on a desired sloped surface by coupling the plurality of male and female connectors 8a and 8b in a lateral direction and a longitudinal direction.
The present inventors have, however, discovered the following disadvantages through experiments involving the mat 1.
(1) The disadvantage is confirmed in which, when skis such as roller skis and caterpillar skis perform edging, the edging causes a force to generate a force in a fall line direction (longitudinal direction) so that the mat 1 is displaced downwardly (i.e., in the longitudinal direction). This is caused by the fact that the mat 1 is overlaid on a ground surface only by the retaining action such as an action of the retainer projections 2 to stick into the ground surface.
When the mat 1 is displaced in the fall line direction, a lower edge of the mat located downwardly is brought into contact with a final edge of the slanted surface to generate creases. Furthermore, after the force is applied in the fall line direction, the mat 1 is pushed upwardly by a reactive force from the final edge of the slanted surface so that the phenomenon occurs in which the mat 1 is lifted or raised. This lift phenomenon is transferred to the upper mat 1. Accordingly, the skiing slope becomes corrugated so that good skiing might not be possible.
(2) Since the mat 1 is made of synthetic resin, a contraction/expansion of the mat 1 due to the variation of the ambient temperature is remarkable. When the surroundings are kept at a low temperature, the mat 1 is shrunk so that tensions are applied to the male connectors 8a and the female connectors 8b of each mat 1. When, in order to replace any one mat laid in the lateral and longitudinal directions by new one, for example, the old mat 1 is removed and the new mat 1 is connected to the mats 1 located right and left and up and down, the replacement work is very difficult since the existing mats have shrunk. (Through repeated experiments, it was confirmed that it was very difficult to perform the connection for the male connectors 8a and the female connectors 8b in the longitudinal direction, but it is not so difficult to perform the connection for the male connectors 8a and the female connectors 8b in the lateral direction.) This is fatal in the maintenance aspect.
After all, it is necessary to again replace all the mats 1 by new ones only for the replacement of the single mat 1.
Also, this system suffers from other disadvantages in that it is difficult to locate the old mat 1 by a new one at high temperature, and the mats 1 are pushed against each other so that the skiing slope as a whole is corrugated or wavy in addition to the affect of the force applied in the fall line direction upon the edging action described in the above-described disadvantage (1).